The invention concerns a pillow-shaped wound care article for the extraction and control of wound fluids as described and claimed herein.
This type of wound care article is especially suitable for the extraction of exudate from chronic wounds, such as (for example) when diabetes, ulcus cruris, and similar illnesses occur.
The term “exudate” designates a wound fluid that is secreted from the blood plasma through the inflammatory processes of the wound oedema. Just as the blood is responsible for the transportation of nutrients and other substances and thus for supplying various parts of the body, the exudate serves in a very similar way to supply the wound bed and the healing processes occurring therein. To perform adequately in these various functions, it contains a broad spectrum of components, resulting in a specific density slightly greater than that of water. This distinguishes it from “transsudate”, which is derived from non-inflammatory processes, and which has a significantly lower specific density with a lesser cell and protein content. In addition to providing nutrients for the fibroblasts and epithelial cells, the exudate coordinates the various processes of local and chronological wound healing, by means of its high concentration of growth factors and cytokines. These are formed primarily by thrombocytes, keratinocytes, macrophages, and fibroblasts. They influence the motility, migration, and proliferation of the various cells involved with healing the wound. Thus the migration of cells into the wound base is promoted, as well as the supply for the newly created granulation tissue through angiogenesis. Wound cleansing is also promoted by the exudate. It contains various serin, cystein, and aspartate proteases, as well as matrix-metalloproteases, which by their strictly regulated activity remove irreversibly damaged tissue, and thus prepare the wound bed for subsequent phases of healing.
Particular components of the physiological exudate are salts, glucose, cytokine and growth factors, plasma proteins, proteases (especially matrix-metalloproteases), granulocytes, and macrophages.
If a significant progression corresponding to the various phases of the wound healing process does not occur within a few weeks, it is called a chronic wound. However, an exudative phase lasting even as long as three days is regarded as a complication, and may be referred to as a pathologic exudation, which may contribute to a chronic character of the wound. The fundamental underlying causes are usually complex and may indeed be of systemic nature. In view of the previously mentioned importance of the exudate for wound healing, it is not surprising, that complications in healing of the wound will be reflected in significantly altered composition and the effects of the exudate.
The exudate, which normally promotes healing, will lose its positive effect for chronic wounds through (among other things) a shift in concentration of the individual components of the exudate. In particular, the concentration of inflammatory cytokines and proteases is significant increased in pathological exudates. Whereas, the concentration of growth factors is reduced. A particularly important difference results in respect to the activity of the matrix-metalloproteases mentioned earlier. In addition to preparing the wound bed, they also take part later in rebuilding the granulation tissue to scar tissue. These enzymes are normally formed as inactive pre-enzymes, and their activity is regulated through corresponding inhibitors (tissue inhibitors of metalloproteases: TIMP's), which even have a simultaneous positive effect for cell growth. In chronic exudate the activity of the proteases seems to be increased because of disturbances in this regulating system, which may contribute to an active regression of the wound. With regard to the concentration of its components, pathological exudate has gotten out of the balance required for a progressive healing of the wound. The leads to various complications, which contribute further to the deterioration and chronic character of the wound.
A wound care article of the type mentioned above serves especially to absorb this mentioned chronic exudate, and thus to promote healing of the wound. The applicant is aware of such a wound care article from Patent DE 100 59 439. In the case of this familiar wound care article, the wound care article's additional, internal enclosure made of cotton has the function to inhibit direct contact between the mucous cells of the patient's wound or body cavity and the absorbent pad. The effect of the wound care article applied on the patient's wound or body cavity—especially the absorptive force acting on the wound—is the same, no matter whether its “left” or “right” side is used.